Conductive Writing with High Precision by Laser-Induced Point-to-Line Carbonization Strategy for Flexible Supercapacitors

Flexible electronic technologies have broad development prospects. Fabrication of micro devices on flexible carbon precursors via laser carbonizing has the advantages of involving only one step, requiring no mask, and wide adaptability. It has attracted significant attention in recent years to fabricate micro devices on polyimide (PI) via laser carbonization. However, the precision of laser carbonization is low because large areas of the material are easily carbonized simultaneously. Thus, the fabrication of micro devices with high precision and narrow line widths via laser carbonization remains challenging. Herein, a laser-induced carbonization method with point-to-line carbonization strategy is proposed and used to fabricate supercapacitors on PI. The carbon line width decreases from over 150 to below 10 µm using this method. High-precision conductive writing is realized on PI. Carbon lines written by this method have low resistance and porous surface. Hence, these carbon structures are suitable as electrodes for supercapacitors. Supercapacitors with microscale electrode widths are fabricated using this method. This work demonstrates that the point-to-line strategy improves the precision of laser carbonization and provides an effective method for fabricating flexible electronics on polymers with high precision.